Re: Strange Reoccuring Bruise..quite nervous!!
If it's the only bruise, I'd try not to worry. If bruises start showing up all over with no known origin, that's when to get concerned. You're probably doing something to cause the bruise and don't realize it.
I wouldn't chalk it up to aging, but I would keep an eye out for other symptoms.
I have ITP - Immune Thrombocytopenia Purpura, where periodically my platelets drop to a low level. This usually leaves me in bruises everywhere- any tiny tap can bruise me, and when I scratch an itch, it leaves tiny red dots - petechiae, which are tiny bruises under the skin from the contact.
My advice is to keep a watch, but don't be too worried.